Loom letoff mechanism



- I.1. o. FOSTER Er A1. 2,435,437

LOOM LET-OFF MECHANISM Filed Feb. 15, 1946 Feb. 3, 194s.

2 Sheets-Sheet 1 JSSI 0. F0675@ @Fd/Q65 R. 62A W50/VA Feb- 3. .1943 .1.0. FOSTER Er AL 2,435,437

LOOM LET-OFF MECHAN-\ISM Filed Feb. 15, 1946 2 sheets-sheet 2 alfa/Q65 A. @A wsa/VA Jfssf 0, Fsrz-'R N9 Patented Feb. 3, 1948 2,435,437 LOOM LETOFF MECHANISM Jesse Odell Foster,

Clawson,

Linwood, and George Rome Salisbury, N. C.

Application February 15, 1946, Serial No. 647,785 4 Claims. (C1. 139-110) 1 This invention relates to looms, `and more particularly to mechanism employed in connection with weaving from beamed warp to let off the yarn at a rate commensurate with the requirements of the Weaving operations.

In existing looms there are two types of letoi motions extensively employed. One type includes mechanism which is governed automatically by the tension of the warp, and the other depending upon friction applied to the warp beam. This Vinvention is to be 4employed in connection with the former type, in which a pawl and ratchet mechanism is utilized to intermittently turn the warp beam to pay out the warp. The amplitude of 'turning movement of the ratchet upon .each stroke of the pawl is regulated by the degree of tension exerted on the warp. The warp beam has a large gear that meshes with a pinion which is turned at a reduced speed by the pawl and ratchet through conventional interposed speed-reducing mechanism, and the warp beam is rotatably mounted upon the loom frame near its rear end vand adjacent to the pawl and ratchet mechanism. Warp yarns from the Warp beam engage a whip roll, and the whip roll is mounted for yielding swinging movement responsive to the tension of the warp yarns. The whip roll is operably connected with the pawl and ratchet mechanism, and also with the operating component of the loom to vary the starting point of the pawl in its drive movement relative to the ratchet to thereby drive the warp beam to turn it suiciently at each pick of the loom to pay out the requisite length of warp yarn to maintain the Warp yarn at the proper tension.

Let-E mechanisms of this type are expensive to install and maintain, especially the' elements which are operably interposed between the whip roll and the ratchet mechanism, and the operating components of the loom. Such let-off mechanism also requires frequent adjustment.

Accordingly, it is an object of this invention to simplify and otherwise improve the let-off mechanism employed in modern looms, and particularly the elements which are operably interposed between the whip roll and ratchet mechanism and the operating components of the loom.

A specific object of the invention is to provide, for use in looms, an improved let-off mechanism which imparts a positive drive to the warp beam to pay out the requisite length of warp yarn at each pick of the loom.

A more specific object of this invention is to provide, for use in looms, an improved let-oil1 Ynzieclianisnci which cooperably connects the whip et 20 which is secured `2l `or other suitable securing devices.

roll and ratchet mechanism directly with an operation component of the loom through `greatly simplified instrumentalities, and to also provide a device which may be readily installed on-existing looms and 'which requires only ua minimum of adjustment in its operation.

It is also an object of this invention to provide, for use in looms, a let-off mechanism of vgenerally improved construction whereby the 4device will be simple, -durable and inexpensive in construction, as well as convenient, practical, vserviceable .and eicient in its use.

and other obiects in View,

.the description proceeds, the combination and ar rangement of parts, and in details of construction hereinafter described and claimed, it being understood that various changes in form, proportion, and minor details .of construction .may be made within the scope of the claims without departing from the spirit or sacriiicing any advantages of the invention.

For a complete disclosure oi the invention, a detailed description oi it will now be given in connection with the accompanying drawings forming a part of the specification, wherein:

Figure 1 is a fragmental side elevation depicting parts of the loom with which the invention is operably associated, and particularly illustrating the improved let-on mechanism embodying this invention;

Figure 2 is a fragmental horizontal sectional view taken on the line 2-2 of Figure 1;

Figure 3 is a similar yenlarged View taken through the composite bracket;

Figure 4 is a side elevation of the bearing component of the composite bracket; and

Figure 5 is a front view of the bearing component.

Referring to the drawings, in which similar reference characters designate corresponding parts, there is depicted a conventional loom frame having loom sides Ill which operably support the components of the loom. A yarn beam Il is carried by a yarn beam shaft l2, which is rotatably mounted in V`r earings I3 'formed in brackets of the loom sides IB, thereby rotatably supporting the 'yarn beam. A'large gear vlli is carried byone oi the warp beam heads I'B provided at one terminal of the yarn beam, and this Vgear meshes with a letoff pinion II'se'cured to a let-off shaft I8 which is rotatably supported in bearings formed in the machine frame and a let-oil bracklto a loom side by bolts .The let- With the foregoing which will appear as the invention resides in vand the worm wheel 22, "mechanism forms Vno part this application'.

whip; rollv 4|, whip roll. A whip roll lever .extends radially fromk a terminal f the whip m11 35 Yemployed in existing looms.

tension linkior rod inV a bearing recess 46. formed inra bearing comwith a body portion 5| formedtherein.

I8 has a worm wheel or gear 22 secured thereto, and this gear meshes with a worm 23 carried by a worm shaft 25, rotatably mounted in the let-off bracket 28. A let-olf hand wheel 26 is keyed or otherwise secured at the upper terminal of the worm shaft, in order that the worm shaft may be manually turned in conformity with the usual practice, and a conventional let-01T friction clamping mechanism 21 engages off shaft A the worm shaft adjacent the hand wheel to place or frice the shaft under predetermined tension tional resistance. The worm shaft 25 has av ratchet wheel 28 keyed or otherwise'. secured thereto adjacent the hand wheel 26, andrlthis ratchet wheel is operably engaged by a .ratchet or pawl 89 pivotally supported on a ratchet'lever 3| which is provided with a bearing Vp'ortion'or eye 32 which engages and oscillates aboutthe.v

worm shaft 25. A speed-reducing mechanifsmis usuallyinterposed between the let-off pinion |'1 but 'inasmuch as this VYof the present invention it has not beenjdepicted in the drawings of Whip roll brackets 33- the machine frame, and hese brackets have bearing recesses 35formed therein to rotatably'receive a Ywhip roll shaft36. Spaced'whip roll arms 31 are rigidly secured to and extend radially from the whip roll shaft, and lthese arms are provided with bearing recesses 38 which rotatably receive a shaft on trunnions 48 extendingaxiallyfrom a thereby rotatably supporting the 42 is secured to and shaftr36,Y and theouter terminal of the whip roll lever is provided with a projecting pin pr stud 43. TheY machine components vhereinbefore disclosed are wellQknown `in the art and fare. extensively templates the provision of simplified mechanism foroperably connecting the whip roll and warp I beamwith operating components of the machine, y whereby the requisite lengthof yarn may be let 01T duringeach pick of theloom. i 'I'he improved let-off mechanism includes a Y45Y which is slidably mounted ponent 41 of acomposite bracket; The bearing component 41 is secured to a supportingrcompovnent 48 of the composite bracket, and theV supporting component Vis,rin turn, secured to a yloom side i0. The bearing component 41 is provided 50 having an 4elongated slot Abearing head 52 forms a part of the bearing component `41 Vand extends at .an angle therefrom, and this head has the bearing recess 46 formed therein to slidably rehereinafter. The supporting formed therein for the reception of bolts or screws 56 which lrigidly secure Y the bracket component 43 to the loom side. Arleg 51l extends perpendicularly from the foot 53,'and the -leg is Vprovided with spaced threaded apertures 58 for the reception of the threaded shanks of screws 68' which extend through the slot 5| formedin theY bearing component body 50thereby'rigi'dly securing the bearing component 41 to thesupporting component 48 in position to operably support the tension link 45.

Y `VVOne 'terminal of the tension link 45 is provided -with threads 6| whichare received in athreaded 4 recess 62 formed in a head or cam follower 63, and a jamb nut 65 engages the threads 6| and the head 63 to thereby securely lock the tension terminal of the tension link is spring adjuster which includes V'or otherwise rigidly secured to .45, and this head has from, which from the outer terminal Vof the whip roll lever 42.

are suitably secured tol` This invention conceive and support the tension link 45, as will be more fullyY disclosed` component 48 is provided with a foot 53 having spaced apertures 55 adjusting screw hand vthe opposed terminal '88 is slidably supported lon the` tension link; 45-V Vsion spring 8| which diam'etrically opposed mentalities.

rated, this separating 36. The downward 'Ijhe head 1| is'provided with a cylindrical recessV 15 in which an adjusting screw 16 is rotatably received, `The adjusting screw 181s held against axial movement relativeto, the head/11| by a collar 11, that Vis rigidly secured to the screw and engages one terminal of the head, and by an wheel 18 which hasy its hub portion rigidly secured to the screw and abutting of the head 1|.` A traveller and it is also threadedlysecured to the adjusting screw 16, whereby rotarylmovement of the screw the hand wheel 18, causes y 16V,Y by manipulating the traveller to move' axially along the tension link 45 to or from'the bearing bracket component 41. V'I'he tension link 45 supports a, helicalextensurrounds the link and is interposed between the vbearing bracket component 41 and the travellerl, so that movement lof the traveller along the tension link 45 will adjust the degree oftension exerted by. the link against the whip roll lever 42. Y l n Y e A cam 82 is secured totheouter terminal of a cam shaft'83, which forms a. conventional compo- .nent of existinglooms and Adrives certain of the -in vconformity with the weaving instrumentalities practice well known to. hose skilled-in theart. The camV 82 is of elliptical congurationghaving high portions- 85 and diametrically opposed low portions` 86, whichA are r operably interposed between the high portions in thereto, so that upon rota-y tion of theshaft 83, thev cam 82 Vwill impart reciprocatoryfmovement to the tension link 45 against the bias of the tension spring 8|, as'V will be more fully explained hereinafter. Y Y

A connecting rod Vorlink 81 has one terminal pivotally secured tothe Yratchet lever Y3| by apap screw 88, for other suitablewsecuring device, and

its opposed terminal is pivotally secured to the t ca m follower head V6 3, as indicatediat 90, yso that reciprocatory movement of the ytension link 45 and cam follower head 631will impart oscillatory fmovement to the ratchet lever3|,fthus `causingY the ratchet 30 to engage and rotate` the. ratchet wheel 28, thereby imparting the ,let-'01T motion to the yarn beam through the interposedinstru- In operation, at each pick ofthe loom thekcon- ,Y ventional harnesses 4separate alternate warp yarns Y torpermit the lling yarnrto be inserted therebetween, and when the warpyarns are thus sepato the warp yarns, thus causing the whip roll V4| to move downwardly aboutthe whip rollY shaft movement of the whip .roll 4| causes the tensionr link 45 .to move vinwardly movement imparts tension Y 'mamar toward the cam 82, and this nwardmovementis resisted bythe bias of the tension spring 8|. Accordingly, by manipulating the hand wheel 18 the requisite degree of tension may be imparted to the warp yarns through the instrumentality of the whip roll, the whip roll supporting membersand the tension link 45. At each pick of the weaving instrumentalities, a high portion 1,35 of the cam is presented to the cam, roller 66 of the follower head 53, thus forcing the tension link 45 outwardly and the whip roll lllV upwardly to` a predetermined position. When the warp yarns are separated to receive the lling yarns, the whip roll l5Y moves downwardly, and the amplitude of this downward movement is determined by the degree of bias exerted by the tension spring 8l and the diameter of the yarn mass on the warp beam. As the diameter ofthe yarn mass on the warp: beam is decreased', the tension of the warp yarns is commensurately increased, sov that during each pick of the loom the whip roll is forced through a greater amplitude of downward movement, thereby causing the ratchet to engage a greater number of teeth on the ratchet wheel,

thus imparting a let-off motion of greater amplitude to the warp beam to compensate for the decreased diameter of the yarn mass. Thus it is seen that the starting of the operable movement of the ratchet relative to the ratchet wheel is determined by the diameter of the yarn mass on the warp beam and the adjustment of the tension spring 8l. The terminal of the upward movement of. the whip roll. however, is predetermined by the high points of the cam, thus causing the amplitude of let-olf motion imparted to the warp beam to be commensurate with the degree of tension exerted on the warp yarns during the operation of the weaving instrumentalities.

Having thus described our invention, what we claim as new and useful is:

1. In a loom provided with a frame operably supporting weaving instrumentalities including a drive shaft rotatable in timed relation with components of the said weaving instrumentalities, a warp beam, a whip roll over which warp yarns from the warp beam are guided, a rockable whip roll shaft, whip roll arms secured to the whip roll shaft and rotatably supporting the whip roll whereby the whip roll is mounted for swinging movement about the whip roll shaft, and a whip roll lever secured to the whip roll shaft, the combination of a movable tension link operably connected with the whip roll lever and operably interposed between it and the drive shaft, a composite bracket having a supporting component secured to the loom frame, a bearing component -secured to supporting component and having a bearing aperture formed therein to slidably receive the tension link, a spring supported by the tension link and having one terminal abutting the bearing component to bias the tension link for movement towards the whip roll to thereby force the whip roll against the warp yarns, adjusting means engaging the opposed terminal of the spring to adjust the degree of bias exerted by the spring against the tension link. a cam rigidly secured to the drive shaft to operably engage the tension link to positively move the whip roll against the warp yarn tension resistance to a predetermined position during each pick of the loom, the extent of movement of the tension link towards the cam during each pick of the loom being determined by the degree of spring tension adjustment and the consequent warp yarn tension exerted against the whip roll, let-off mechanism spring against the tension link,

operably connected with the warp. beam, and means: for operably connectingy the tensionv link with an operating componentof the let-off mechanism whereby movement of given amplitudev of the-tension link imparts movement of commensurate. amplitude to the let-off mechanism to let off the requisitev length of warp yarn at each pick of therloom.

2. In a loom provided with weaving instrumentalities including a drive shaft rotatable in timed relation with components of the said weaving instrumentalities, a warp beam, a whip roll over which warp yarns from the warp beam are guided, a. rockable whip roll shaft, whip roll arms secured to the'. whip roll. shaft and rotatably supporting the whip roll whereby the whip. roll is mounted for swinging movement about and ar whipfroll lever secured to the whip roll shaft, the combination of a movablel tension link operably connected with the' whip roll lever and operably interposed between it and the drive shaft, a spring for biasing the tension link for movement towards the whip roll lever to thereby force the whipY roll againstv the warp yarns, means for adjusting the degree of bias exerted by the spring against the tension link, a follower head rigidly secured to the inner terminal of the tension link, a cam roller operably supported by the follower head, a cam rigidly secured to the drive shaft to. operably engage the cam roller to positively move the whip. roll against the warp yarn tension resistance to a predetermined position during each pick of the loom, the extent of move.. ment of the tension link towards the cam during each pick of the loom being determined by. the degree of spring tension adjustment and the consequent warp yarn tension exerted against the whip roll, let-off mechanism operably connected with the warp beam, and means for operably connecting the follower head of the tension link with an operating component of the let-olf mechanism whereby movement of given amplitude of the tension link imparts movement of commensurate amplitude to the let-off mechanism to let off the requisite length of warp yarn at each pick of the loom.

3. In a loom provided with weaving instrumentalities including a drive shaft rotatable in timed relation with components of the said weaving instrumentalities, a warp beam, a whip roll over which warp yarns from the warp beam are guided, a rockable whip roll shaft, whip roll arms secured to the whip roll shaft and rotatably supporting the whip roll whereby the whip roll is mounted for swinging movement about the whip roll shaft, and a whip roll lever secured to the whip roll Y shaft, the combination of a movable tension link operably connected with the whip roll lever and operably interposed between it and the drive shaft, a spring for biasing the tension link for movement towards the whip roll lever to thereby forc the whip roll against the warp yarns, means for adjusting the degree of bias exerted by the a follower head rigidly secured to the inner terminal of the tension link, a cam roller operably supported by the follower head, a cam rigidly secured to the drive shaft to operably engage the cam roller to positively move the whip roll against the warp yarn tension resistance to a predetermined position during each pick of the loom, the extent of movement of the tension link towards the cam during each pick of the loom being determined by the degree of spring tension adjustment and the consequent warp yarn tension exerted against the the whip roll shaft,

whip roll, let-olf mechanismoperably connected with the warp beam, and a connecting rod for operably connecting the follower head of the tension link with an operating component of the let-oir mechanism whereby movement of given amplitude of lthe tension link imparts movement of commensurate amplitude to the let-oil mechanism to let oi the requisite length of warp yarn at each pick of the loom.V u l 4f In a loom provided with weaving instrumentalities including a'drive shaft rotatable in timed relation with componentsV of the said weaving instrumentalities, a warp beam, a whip roll over which warp yarns from the warp beam are guided, a rockable whip roll shaft, whip roll arms secured to the whip roll shaft and rotatably supporting the whip roll whereby the whip roll is mounted for swinging movement about the whip roll shaft,

Vand a Whip roll lever Vsecured to the whip roll shaft, the'comb'ination of a movable tension link operably connected with the whip roll lever and operably interposed between it and the drive shaft,` a spring vfor biasing the tensionlink for movement towardsA the whiproll lever to thereby force the whip roll against the warp yarns, means Yfor adjusting thedegree of bias exerted bythe spring against'the 'tension link, a follower'head rigidly 'secured to the inner terminal of the tension link, a' cam rolleroperably supported by the follower head, a camrigidly secured to the drive shaft to operably engage the cam roller to positively move the whip roll against the warp 'yarn tension resistance to a' predetermined position `during each pick of the loom, the extent of movement of the tension link toward the cam during each pick of the loom being determined by the degree of spring tension adjustment and the 8 consequent warp yarn tension exerted against the whip roll, a rotatable worm shaft operably connected with the warp beam through Yinter-- posed instrumentalities whereby rotation of the worm shaft imparts rotary movement tothe Warp beam, a ratchet wheel secured to and rotatable with the worm shaft, a ratchet lever mounted for oscillatory movement about the worm shaft,-a ratchet pivotally secured to the ratchet lever and operably engaging the ratchet wheelv to impart rotary movement inV one direction tothe worm shaft of amplitude commensurate with the'amplitude of oscillatory'movement of the ratchet lever, and a connecting'rod having one terminal pivotally connected with the follower head of the tension link and its 'Y opposed terminal pivotally connected with the ratchet lever whereby movement of given amplitude of the tension link imparts movement vof commensurate amplitude to the worm shaft and warp beam to let 'o the requisite length of Warp yarn at each pick of the loom.

JESSEV ODELL FOSTER. GEORGE ROME CLAWSON. Y

REFERENCES CITED AThe following references are of Vrecord in the le of Vthis patent;

UNITED STATES Pig-rubricY Number Name Date 647,815 Draper Apr. 17, 1900 A 954,648 Rhoades Apr. 12, 1910 1,116,400 Farnsworth Nov.'10, 1914 4 1,586,982 Epps June 1, 1926 1,749,120 Baker Mar. V4, 1930 

